Background: Cytomegalovirus (CMV) infection remains a major cause of morbidity, mortality, and increased healthcare burden in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Its clinical manifestations range from asymptomatic CMV replication to end-organ diseases such as pneumonia, gastroenteritis, and retinitis, all of which are associated with a higher rate of nonrelapse mortality. Methods: We reviewed case records of children who underwent allo-HSCT at our center between April 2013 and October 2024. CMV monitoring was performed weekly until at least day +100 post-HSCT using a quantitative polymerase chain reaction assay. All patients received acyclovir prophylaxis. Pre-emptive intravenous ganciclovir therapy was initiated when CMV-DNA levels exceeded 500 IU/mL Results: A total of 150 consecutive patients (58% male) were included. The median age at HSCT was 6.3 years (interquartile range [IQR], 3.4–11.3 years). Indications for HSCT were hematologic malignancy (n=81, 54.0%), inborn errors of immunity and bone marrow failure (n=46, 30.7%), and hemoglobinopathy (n=23, 15.3%). Donor and recipient CMV seropositivity rates were 86.7% and 94.0%, respectively. CMV infection occurred in 43.4% of patients, with a median onset of 30 days post-HSCT (IQR, 21–47 days). There were five (3.3%) cases of CMV disease, resulting in one (0.7%) CMV-related death. Human leukocyte antigen (HLA)-haploidentical donor status (odds ratio [OR], 5.00; 95% confidence interval [CI], 2.43–10.29; P<0.001) and the use of serotherapy in the conditioning regimen (OR, 2.87; 95% CI, 1.47–5.60; P=0.002) were significantly associated with an increased risk of CMV infection. Conclusions CMV infection was a common occurrence, particularly among patients with HLA-haploidentical donors. Preventive strategies such as weekly surveillance and pre-emptive ganciclovir therapy proved effective in preventing overt CMV disease.

INTRODUCTIONChildren with Down syndrome (DS) are at increased risk of developing distinctive clonal myeloid disorders, including transient abnormal myelopoiesis (TAM) and myeloid leukaemia of DS (ML-DS). TAM connotes a spontaneously resolving congenital myeloproliferative state observed in 10%-20% of DS newborns. Following varying intervals of apparent remission, a proportion of children with TAM progress to develop ML-DS in early childhood. Therefore, TAM and ML-DS represent a biological continuum. Both disorders are characterised by recurring truncating somatic mutations of the GATA1 gene, which are considered key pathogenetic events.

METHODSWe herein report, to our knowledge, the first observation on the frequency and nature of GATA1 gene mutations in a cohort of Malaysian children with DS-associated TAM (n = 9) and ML-DS (n = 24) encountered successively over a period of five years at a national referral centre.

RESULTSOf the 29 patients who underwent GATA1 analysis, GATA1 mutations were observed in 15 (51.7%) patients, including 6 (75.0%) out of 8 patients with TAM, and 9 (42.9%) of 21 patients with ML-DS. All identified mutations were located in exon 2 and the majority were sequence-terminating insertions or deletions (66.7%), including several hitherto unreported mutations (12 out of 15).

CONCLUSIONThe low frequency of GATA1 mutations in ML-DS patients is unusual and potentially indicates distinctive genomic events in our patient cohort.

Cohort Studies ; Down Syndrome ; complications ; genetics ; Exons ; Female ; GATA1 Transcription Factor ; genetics ; Gene Deletion ; Genomics ; Humans ; Infant, Newborn ; Leukemia, Myeloid ; complications ; genetics ; Leukemoid Reaction ; complications ; genetics ; Malaysia ; Male ; Mutation ; Referral and Consultation ; Remission Induction

Immune thrombocytopenia is the most common diagnosis of isolated thrombocytopenia. The dilemma encountered by paediatricians is missing diagnosis of acute leukaemia in children with isolated thrombocytopenia. We demonstrated childhood ITP could be diagnosed using a four point clinical criteria without missing a diagnosis of acute leukaemia. Hence, bone marrow examination is not necessary in children with typical features compatible with ITP prior to steroid therapy. This can encourage paediatricians to choose steroid therapy, which is cheaper and non-blood product, as first line platelet elevating therapy in children with significant haemorrhage.
Thrombocytopenic

Background & Objective: Posterior reversible encephalopathy syndrome (PRES) is associated with immunosuppressive agents used in children with haemato-oncological diseases. There are no reports to date from the South Asia and South East Asia region. We report a Malaysian tertiary centre case series of children with haemato-oncological disease who developed PRES. Methods: Retrospective study of children seen with haemato-oncology diseases seen at the University Malaya Medical Centre Kuala Lumpur who developed PRES from 2011 – 2013. Clinical details were obtained from medical records and brain neuroimaging was reviewed. Results: Five patients met the inclusion criteria. All 5 patients had significant hypertension acutely or subacutely prior to neurology presentation. Four presented with acute seizures and the remainder 1 presented with encephalopathy.Three patients were on chemotherapy, 1 had renal impairment and 1 had prior immunosupression for bone marrow transplantation. A full recovery was seen in 4 patients and 1 patient had mild residual quadriplegia. Conclusion: Our case series expands the clinico-radiological spectrum of PRES in children with underlying haemato-oncological disorders. It is the first to show that prior cyclosporin intake as long as 2 months is a potential risk factor for PRES. Clinicians need to be vigilant for development of PRES and closely monitor the blood pressure in these children who are receiving or recently had immunosuppressive drugs and present with acute neurological symptoms.
Posterior Leukoencephalopathy Syndrome ; Brain Diseases

In childhood acute lymphoblastic leukaemia (ALL), cytogenetics play an important role in diagnosis, allocation of treatment and prognosis. Conventional cytogenetic analysis, involving mainly karyotyping in our experience, has not been successful in a large proportion of cases due to inadequate metaphase spreads and poor chromosome morphology. Our aim is to develop a highly sensitive and specific method to screen simultaneously for the four most frequent fusion transcripts resulting from specific chromosomal translocations, namely, both the CML- and ALLtype BCR-ABL transcripts of t(9;22), E2A-PBX1 transcript of t(1;19), the MLL-AF4 transcript of t(4;11) and TEL-AML1 (also termed ETV6-CBFA2) of the cryptic t(12;21). A multiplex reverse transcription polymerase chain reaction protocol (RT-PCR) was developed and tested out on archival bone marrow samples and leukaemia cell lines. In all samples with a known translocation detected by cytogenetic techniques, the same translocation was identified by the multiplex-PCR assay. Multiplex RT-PCR assay is an effective, sensitive, accurate and cost-effective diagnostic tool which can improve our ability to accurately and rapidly risk-stratify patients with childhood ALL.
Child ; Humans ; Oncogene Proteins, Fusion ; genetics ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Translocation, Genetic